Each year during Ashoura, Shiite Muslim men & boys whip their backs with chains and cut their heads with knives, drenching themselves in blood to mourn the loss of one of the faith's most revered figures, Imam Hussein, a grandson of the Prophet Mohammad, who was killed in the 7th century battle of Kerbala.

Thaier Al-sudani / Reuters

Shiite Muslim worshippers, covered in their own blood from self-inflicted wounds, hold knives during a procession to mark the Muslim festival of Ashoura in Baghdad's Sadr City on Nov. 24.

Thaier Al-sudani / Reuters

An Iraqi Shiite Muslim child gashes his forehead with a sword during a ceremony marking Ashoura in Baghdad's Sadr City on Nov. 24.

Murad Sezer / Reuters

Turkish Shiite women during an Ashoura procession in Istanbul on Nov. 24.

Dar Yasin / AP

Blood runs down the face of a Kashmiri Shiite Muslim as he participates in a procession in Srinagar, India, on Nov. 24.